Synthesis, structure and DNA-binding studies on the 2-(3-chlorophenyl)imidazo[4,5-f]1,10-phenanthroline-bis(2,2 '-bipyridine)-ruthenium(II) complex

A new polypyridyl ligand, MCP {MCP = 2-(3-chlorophenyl)imidazo[4,5-f]1,10-p henanthroline} and its ruthenium(II) complex, [Ru(bpy)(2)(MCP)](ClO4)(2). 0 .5MeCN (bpy = 2,2'-bipyridine), have been synthesized and characterized. Th e structure of the complex was determined by single crystal X-ray diffracti on techniques. The MCP ligand is essentially planar and the stacking intera ctions between the ligands were observed in the crystal. [Ru(bpy)(2)(MCP)]( 2+) can strongly bind to Calf thymus DNA through intercalation of MCP ligan d. The Cl substitute group has no significant effect on the spectral proper ties and DNA-binding behaviour of the complex.